Reinforced-concrete slab construction.



C. A.P. TURNER.

REINFORCED CONCRETE SLAB CONSTRUCTION.

APPLICATION FILED JAN.18, 1912.

1,131,019. Patented Mar. 9, 1915.

l5 INVENTOR THE NORRIS PETERS CO.. PHOTO-LITHO.. WASHINGIDN. D. c

CLA UDE A. 1?. TURNER, OF MINNEAPOLIS, MINNESOTA.

REINFORCED-CONCRETE SLAB CONSTRUCTION.

Specification of Letters Patent.

Patented Mar. 9, 1915.

Application filed January 18, 1912. Serial No. 671,920.

To all wiz am it may concern Be it known that I, CLAUDE of Minneapolis, in the county of Hennepin, and in the State of Minnesota, have invented a certain new and useful Improvement in Reinforced-Concrete Slab Construction, and do hereby declare that the following is a full, clear, and exact description thereof.

My invention relatesto the type of construction now commonly known as the mushroom and for which I have obtained Letters Patent of the United States including'No. 1,003,384, September 12, 1911, and my object is to provide an arrangement of slab reinforcement that will conduce to economy of both metal and concrete in buildings of a certain class and where floor spans of oblong shape are required, and to this end my invention consists in the arrangement hereinafter specified and claimed.

In the accompanying drawings-Figure 1 is a top plan view in the nature of a diagram illustrating a section or portion of a floor slab reinforcement embodying my inventiofi; Fig. 2 is a vertical section on the line 2-2 of Fig. 1; Fig. 3 is a detail view in vertical section on a larger scale through the slab at one of the columns.

In the mushroom or beamless flat slab type of construction, the slab with a floor or roof is supported directly upon the columns without the intervention of beams or girders, this arrangement being possible by reason of the arrangement of the reinforcement with reference to the columns and to the slab so that there is such coaction or combination between the reinforcement and the concrete that the slab may be of minimum thiclmess due to its acting as a continuous mathematical flat plate, and where buildings of a heavy type, or where heavy loads are to be carried are designed, the preferable arrangement is one in which the columns are arranged four square so that the panels are square or practically square in form. In buildings intended for light loads, such as office buildings and public buildings and buildings where provision must be made for hallways, the square arrangement of columns is not feasible, and the panels must assume an oblong form, and my present invention is to meet this special condition and with economy of both steel and concrete.

As may best be seen by reference to Fig. l of the drawings wherein each group of concentric circles indicates the location of the A. P. TURNER,

columns A, I run the reinforcement 10, which as shown, is in the form of groups or belts of parallel rods from column to column on the oblique or diagonal lines, not from one column to the nearest column on the diagonal line, but to the next column beyond, or to the alternate column, so that, considering two adjacent oblong panels each group or belt of diagonal reinforcement between two columns crosses two panels in the direction of the shorterdimension of the panel. Besides the obliquely or diagonally extending belts'or lines of reinforcements, there are lines or belts of reinforcement extending from column to column in the two shorter distances so that each oblong panel has two parallel groups or belts of reinforcement 11 forming its longer sides, and two parallel groups or belts of reinforcement 12 forming its two shorter sides. It is important to secure the maximum economy both'in concrete and metal to avoid too acute an angle between the various lines of reinforcement, and in accordance with my present invention such angle may be kept suliiciently great to secure that maximum economy.

The groups or belts of reinforcement are, to secure the best results, of such width that the entire area of the slab between the columns or points of support is traversed by reinforcement.

The groups or lines of reinforcement extending through the slab B are located in the tensile zone of the slab, that is toward the top of the slab above the neutral axis at the columns, and toward the bottom of the slab, below the neutral axis, between the columns, and the intersection of the lines or belts of reinforcement over the columns forms thereat a circumferential cantaliver head. Preferably at the columns a supplemental cantaliver frame is employed which may have various forms, but which, as shown in the drawings, consists of several concentric rings 13, that rest upon the out bent ends 14:, of reinforcing rods 15 situated in the columns.

I prefer to run through the slab parallel with the belts or groups of rods running on the short sides of the panel, a group or belt of reinforcement 16, which crosses the points of intersection of the diagonally or obliquely extending belts of rods midway between the lines of columns as thereby the various intersections are tied together and all the panels act as one or a continuous monolith.

While I prefer reinforcement in the form of belts of rods, by reason of certain practical advantages the scope of my invention is to be understood as extending to other forms of reinforcement.

Having thus described my invention. what I claim is- 1. An arrangement of reinforcement for a column supported fiat floor slab, the combination of groups of columns arranged to form oblong'panels each supported by a group of four columns, belts of reinforcement extending from column to column upon the sides of the panel formed by a group of four columns, and belts of reinforcement extending obliquely from column to column, the obliquely extending belts. reaching froma column of one panel to the column of a panel beyond, said belts being in the zone of tension above the columns and between the columns.

2. In an arrangement of reinforcement for a column supported fiat floor slab of concrete, the combination of groups of columns arranged to form oblong panels each supported. by a group of four columns, belts of reinforcements extending from column'to column upon the sides of the panel formed by a group of four columns, and belts of reinforcement extending obliquely from. column to column, the obliquely extending.

belts reaching from a column of one panel to the column of apanel beyond, and a belt of reinforcement extending parallel with the belts forming the shorter sides of the panels and crossing the obliquely extending belts where they intersect, said belts being in the zone of tension above the columns and between the columns.

3. In an arrangement of reinforcement for a column supported fiat floor slab of con- Copies of this patent maybe obtained for five cents each, by addressing the Commissioner of Patents,

crete, the combination of groups of col umns arranged in parallel lines, the lines.

being farther apart than the distance between adjacent columns of a line, belts of reinforcement crossing the columns in the direction of the lines of columns, beltsbf reinforcement crossing the columns at right:

angles to such lines, and belts of reinforcement extending from the columns. of one an oblique belt extends being the alternate columns ofthe respective'lines, said belts being in the zone of tension above the columns and between the columns.

4c. In an arrangement of reinforcement for a column. supported flat floor slab of concrete, the combination of groups of columns arranged in parallel lines, the lines being farther apart than the distance between to the columns of the other line in an oblique direction, the columns between which an oblique belt extends being the alternate columns .of the respective lines, and a beltof reinforcement midway between the lines or columns and parallel therewith, said belts being in the zone of tension above the columns and between thecolumns.

In testimony that I claim the foregoingI have hereunto set myhand.

CLAUDE A; P. TURNER.

lVitnesses A. T. WIIK, PIERCE P. FU1RBER.

'59 line to the columns of the other linein 'anoblique direction, the columns between which 

